I bought a 3gs a few days a go. It cames with FW 3.1.2 Boot 5.11.07 and jbkd by apple store. i install cidya by redsnow and made it rain and all look ok the face of Geohotz appears but when the phone finished in the screen there was just was the itunes and cidya icons nothing more.... oh noooooooooo i screwe my iphone. i started cidya and i tink this save my shsh file on it.

i tried restore the 3.1.2 but i cant. then i made a 3.1.3 custom on pwnage tool 3.1.5. Then i restore my iphone with the custom fw but when itunes finished my iphone get stuck in Black Screen... Now i dont know what can i do.... PLZ HELP ME!!!

Sounds like you messed up your phone pretty bad. When you jailbreak, you should ever only use one tool. Redsn0w or blackra1n or pwnagetool. Not several of them at the same time. There's no need to and worst case scenario is that you're forced to restore.

I'm guessing there's no other option than restore to a clean 3.1.3 and wait until a new jailbreak is released.